Direction controllable lighting unit with ultrasound

1. A direction controllable lighting unit including at least one direction controllable lighting unit, comprising: a mechanically movable element for directing a light emission into different directions along a light emission output axis; at least two ultrasound receiver units disposed at said movable element; wherein said at least two ultrasound receiver units are disposed at said lighting unit in such a way that they differ in at least one of: position, direction of spatial intensity distribution of emission, shape of spatial intensity distribution of emission, direction of spatial distribution of reception sensitivity, or shape of spatial distribution of reception sensitivity and are offset from said light emission output axis; said ultrasound receiver units are operable to receive distinguishable ultrasound signals; a mobile control element including at least one ultrasound transmitter unit; and a controller to evaluate a signal transmitted at the at least one receiver units, wherein a difference between signals of different receiver units received at the receiver unit is used to determine a relative direction of said direction controllable lighting unit and said mobile control element and to control the direction of said controllable lighting unit dependent on said relative direction.

2. The direction controllable lighting unit according to claim 1 wherein said movable element for directing a light emission includes a driver to control a plurality of light sources facing in different, fixed directions to direct a resulting sum light emission, wherein said sum light emission is directed by controlling a relative intensity of light emission from said light sources.

3. The direction controllable lighting unit according to claim 1 wherein said control element is disposed to control said controllable lighting unit such that its direction is adjusted to point to the position of said mobile control element.

4. The direction controllable lighting unit according to claim 1 wherein said controller is disposed to evaluate said difference relating to at least one of phase or amplitude of said signal.

5. The direction controllable lighting unit according to claim 4 wherein both said signals are received at said receiver units, wherein said controller is disposed to analyze at least one parameter relating to a difference between said signals, where said parameter is dependent on at least one of phase or amplitude of said signals, and wherein said signals are distinguishable by the use of a time, code and/or frequency multiple access technique.

6. The direction controllable lighting unit according to claim 1 wherein said controller is disposed to activate said ultrasound receivers only in a direction control mode of said lighting unit, where the direction is to be adjusted, and to deactivate said-ultrasound receivers in an operating mode, where adjusted direction is held constant for lighting operation.

7. A direction controllable lighting unit including at least one direction controllable lighting unit comprising a mechanically movable element for directing alight emission into different directions along a light emission output axis; at least two ultrasound receiver units disposed at said movable element for moving therewith, wherein said a least two ultrasound receiver units are disposed at said lighting unit in such a way that they differ in at least one of: position, direction of spatial intensity distribution of emission, shape of spatial intensity distribution of emission, direction of spatial distribution of reception sensitivity, or shape of spatial distribution of reception sensitivity and are offset from said light emission output axis, said ultrasound receiver units are operable to transmit distinguishable ultrasound signals, a mobile control element including at least one ultrasound transmitter unit, and control means to evaluate a signal received at the receiver units, wherein a difference between signals of different receiver units is used to determine a relative direction of said direction controllable lighting unit and said control element, and to control the direction of said controllable lighting unit dependent on said relative direction.

8. The direction controllable lighting unit according to claim 7 wherein said movable element for directing a light emission comprise driving means to control a plurality of light sources facing in different, fixed directions to direct a resulting sum light emission, wherein said sum light emission is directed by controlling a relative intensity of light emission from said light sources.

9. The direction controllable lighting unit according to claim 7 wherein said control means are disposed to control said controllable lighting unit such that its direction is adjusted to point to the position of said mobile control element.

10. The direction controllable lighting unit according to claim 7 wherein said control means is disposed to evaluate said difference relating to at least one of phase or amplitude of said signal.

11. The direction controllable lighting unit according to claim 10 wherein both said signals are received at said receiver units, wherein said control means are disposed to analyze at least one parameter relating to a difference between said signals, where said parameter is dependent on at least one of phase or amplitude of said signals, and wherein said signals are distinguishable by the use of a time, code and/or frequency multiple access technique.

12. The direction controllable lighting unit according to claim 7 wherein said control means is disposed to activate said ultrasound receiver only in a direction control mode of said lighting unit, where the direction is to be adjusted, and to deactivate said ultrasound receiver in an operating mode, where adjusted direction is held constant for lighting operation.